I am planning on going to Canada (as a citizen) and apply to sponsor my husband there...how can he be able to come with me and stay there legally untill all the paper work is approved?
Your husband does not need a tourist visa to come to Canada if he is a Portuguese citizen. What you should do is prepare your documentation (marriage certificate and translation, shared accounts, etc) and bring it with you when you fly to Canada. After entering Canada, you can apply for "Inland Sponsorship" and he can apply for an "open work permit".
With which countries does this process work similarly? For example, if I were to marry a Russian woman in Russia, would this work the same way? Just fly back to Canada with her and then apply for inland sponsorship?
Well, if you married a Russian woman, the Russian woman would need a visa to come with you. But once you got here, you would tell the CBSA (border guards) that you are sponsoring her, and they should let her in.
And I misspoke about applying at the port of entry. You merely tell them at the port of entry that you intend to apply, and then apply once you are in Canada.